Volume 16 - 2014

Extreme floods often demonstrate unanticipated characteristics that pose problems for management and response. The flood in the Stratoni region in February 2010 provided an example of such unexpected response. The aim of this paper is the quantification of the hydrologic response of the torrents that outfall in the area of Stratoni of the prefecture of Chalkidiki by means of the synthetic unit hydrograph method. For this purpose, the effective rainfall is estimated with a Curve Number of Soil Conservation Service (SCS) procedure. In addition, the flood hydrograph is estimated using the Sierra Nevada’s synthetic unit hydrograph procedure. The resulting maximum flood discharge was compared with the value obtained by the method of flood-water traces and found not to differ significantly. Understanding of the hydrological operation of floods in small watersheds helps towards the design of plans and constructions of the infrastructure against flood risk. 

PM_2.5 samples were collected from the exhaust stacks on the roofs of a university canteen, a charcoal-grilled chicken restaurant and a wood-oven roasted piglet restaurant. The use of thick exhaust hood filters and also gas and electricity as energy sources for cooking in the kitchen of the university canteen contributed to the emission of much lower PM_2.5 levels (24-127 µg m^-3) compared to the restaurants. The charcoal-grilled chicken restaurant emitted particles at concentrations from 26 to 127 mg m^-3. In the exhaust of the wood-oven roasted piglet restaurant, PM_2.5 ranged from 192 mg m^-3, when vine cuttings were used to fire up the ovens, to 203 µg m^-3, at the final stage of roasting. Organic carbon (OC) represented, on average, 49% of the PM_2.5 mass in samples from the canteen, while elemental carbon (EC) accounted for 1-6%. The OC and EC contents in aerosols from the charcoal-grilled chicken restaurant ranged from 73 to almost 95% and from 0.4 to 1%, respectively. Very high organic contents in the smoke exhausted from the piglet restaurant were also determined. However, the EC mass percentages in PM_2.5 from this restaurant are higher than those found in samples from the other establishments.

A method is presented and preliminarily applied to the optimization of the allocation of oil-slick combating coastal stations in a coastal basin. The decision support methodology is based on the annual simulation of the circulation in the basin according to climatologic data, on the oil spill simulation by the method of Lagrangian particles, on the analysis of the quantified stochastic environmental effects from a number of probable oil spill sources distributed over the basin and on the selection of the optimal coastal oil spill stations. The selection is based on a proposed metric for the operational effectiveness of each station. Using available data, a preliminary application is presented for the Azov Sea, where a number of coastal sites, protected by Ramsar convention, exist and an intensive maritime traffic is planned for the near future.

The three different electrochemical processes are discussed, their efficiencies compared and evaluated. The initial dye concentration of 100 mg l^-1 was fast and efficiently removed in only a few minutes of electroprocessing time. The electro-Fenton treatment is the fastest, most efficient and economical process operated at very low current densities of 0.33 and 0.66 mA cm^-2 and consuming only 4.75x10^-3 and 5.23x10^-3 kWh m^-3 of treated solution respectively. The electrocoagulation treatment with iron electrodes and the electrooxidation process with Ti/Pt electrodes conducted at applied current densities of 5 mA cm^-2 consumed 0.511 and 0.825 kWh m^-3 of treated solution respectively. The proposed procedure is a safe, economical and efficient method for removal of indigo carmine dye from aqueous solutions and dye house effluents.